$(a)$ Why do we jerk wet clothes before spreading them on a clothesline?
$(b)$ Fruits fall off the branches when a strong wind blows. Give a reason.

(N/A) When we jerk wet clothes,the clothes suddenly come into motion,but the water droplets in them tend to remain in a state of rest due to the inertia of rest. As a result,the water droplets get detached from the fabric,causing the clothes to dry more quickly.
$(b)$ Initially,both the fruits and the branches are in a state of rest. When a strong wind blows,the branches suddenly come into motion,but the fruits tend to remain in a state of rest due to the inertia of rest. Consequently,the fruits get detached from the branches and fall down.